CN108392378B - Lower limb rehabilitation training exoskeleton system and its walking control method and hip joint structure - Google Patents

Abstract

The invention relates to an exoskeleton system for rehabilitation training of lower limbs, a walking control method thereof and a hip joint structure, belonging to the technical field of medical robots. The hip joint structure includes the abduction degree of freedom underactuated mechanism, the abduction degree of freedom underactuated mechanism includes the mount, the left hip joint adduction drive arm, the right hip joint adduction drive arm and the driver; the left hip joint adduction drive arm and the right hip joint adduction drive arm The hip joint adduction driving arm can be installed on the mounting seat to reciprocate and swing between the adduction single leg support position and the less abduction position; the driver is used to drive the two hip joint adduction driving arms during the single leg gait cycle The swing side remains in the underabducted position, and the support side moves adducted. The hip joint based on this structure can avoid the problem of rollover during rehabilitation training, and can be widely used in rehabilitation training for patients with lower limb weakness or hemiplegia.

Description

Lower limb rehabilitation training exoskeleton system and its walking control method and hip joint structure

technical field

The invention relates to the technical field of medical robots, in particular to an exoskeleton system for rehabilitation training of lower limbs, a walking control method thereof and a hip joint structure.

Background technique

With the increase in the prevalence of stroke in my country, early rehabilitation training for stroke patients has received more and more attention. The mainstream is to use the plasticity of the central nervous system to make the affected side respond accordingly through exercise training, improve muscle tension, and establish New compositional relationships of the nervous system. However, relying on physical therapists to perform manual rehabilitation training for patients is not only inefficient, but also the effect of rehabilitation training mainly depends on the experience of physical therapists.

With the continuous development and progress of robot technology, the use of exoskeleton robots to replace traditional physical therapists to guide patients in rehabilitation training will help the scientific and quantitative management of patients' rehabilitation training process and solve the problem of insufficient resources for rehabilitation training physical therapists. At the same time, compared with the earlier suspended weight-reducing rehabilitation training exoskeleton based on movable flat boards, the upright walking lower limb rehabilitation training exoskeleton enables patients to truly perceive normal walking under the condition of upright walking instead of standing on the treadmill. Stepping and walking can better assist stroke patients to achieve lower limb rehabilitation training.

The patent document with the publication number CN103932870A discloses a bionic designed lower limb rehabilitation training exoskeleton, which includes a waist tightening mechanism connected to the wearer's waist and lower limb exoskeleton push rods. degrees of freedom; among them, the hip joint achieves three degrees of freedom through the hip joint adduction and abduction mechanism, the hip joint flexion and extension mechanism, and the hip joint internal rotation and external rotation mechanism, and the axes of the three degrees of freedom are orthogonal to the movement of the human hip joint Center; the rotation center of the knee joint flexion and extension mechanism moves together with the rotation center of the human knee joint. The exoskeleton system for lower limb rehabilitation training analyzes the physiological movement characteristics of the hip joints and knee joints of the human lower limbs, and designs the exoskeleton joints accordingly, so that the movement trajectory of the exoskeleton joint rotation center and the human body's corresponding joint rotation center in the process of walking wearing the exoskeleton Being consistent helps improve wearing comfort.

However, the exoskeleton system for lower limb rehabilitation training and other existing exoskeleton systems have the following problems, that is, in clinical trials, when a hemiplegic patient wearing an exoskeleton is supported by one leg, the other leg is about to step forward from the ground , because the patient lacks the ability to actively lift the hips and legs, an exoskeleton is needed to guide the patient's lower limb joints to flex and extend. Under the action of gravity, the human body will overturn to the side where the leg is about to be stepped, causing the wearer to fall sideways. Based on the walking balance and stability Theoretical analysis shows that the main reason is that the Zero Moment Point (ZMP) balance criterion is not satisfied, that is, when the sole of the foot on the side of the leg is about to leave the ground, the exoskeleton robot lacks the active power of hip joint adduction and abduction. For the drive mechanism, there is no angular change in this degree of freedom, causing the ZMP position to be outside the plantar support plane, so there will be an additional overturning moment that causes instability, causing the ZMP position to be outside the plantar support plane, so there will be an additional The overturning moment causes the wearer to lose stability and fall.

Aiming at the above instability problems, the commonly used solution is to use crutches to assist the lower limb rehabilitation series of exoskeleton systems to support human walking, so as to achieve the purpose of ensuring the balance of human walking. Usually, a force sensor is installed at the end of the crutches for Auxiliary detection of the patient's balance state. Although this method of assisting balance with the help of crutches can improve the balance and stability of patients walking after wearing an exoskeleton to a certain extent, it has certain requirements for the ability of the patient's upper limbs to operate crutches, and requires them to be able to adjust in time according to their own balance. The support position of the crutches. This is obviously not easy to achieve for hemiplegic patients after stroke, because hemiplegic patients also have one side of their upper limbs in a paralyzed state.

Contents of the invention

The main purpose of the present invention is to provide a walking control method for the lower limb rehabilitation training exoskeleton system, to ensure that the exoskeleton system can assist the wearer to perform walking rehabilitation training more smoothly; another purpose of the present invention is to provide a lower limb rehabilitation training The hip joint structure used by the exoskeleton system, so that the exoskeleton system for lower limb rehabilitation training can be applied to the above-mentioned walking control method, and can more smoothly assist the wearer to perform walking rehabilitation training; The lower extremity rehabilitation training exoskeleton system constructed by the hip joint structure can assist the wearer to perform walking rehabilitation training more stably.

In order to achieve the above main purpose, the walking control method of the lower limb rehabilitation exoskeleton system provided by the present invention includes an identification step and a control step; the identification step includes identifying the supporting side leg and the swinging side leg of the exoskeleton system in the single-leg gait cycle; controlling The steps include controlling the hip joint on the swing side to maintain a state of underabduction during the swinging movement of the swing leg, and controlling the hip joint on the supporting side to adduct to meet the zero-moment point balance criterion during the single-leg support of the supporting leg.

During the walking process of the exoskeleton system, by controlling the hip joint on the swing side to be under abduction during the swing process of the leg on the swing side, and controlling the adduction action of the hip joint on the support side, it is similar to the adduction of the normal person walking in the prior art. Compared with the control method of abduction and abduction, it is easy to shift the overall center of gravity of the wearer and the exoskeleton system to the plantar support surface of the supporting leg, so as to meet the zero-moment point balance criterion, which can effectively avoid its The problem of rollover under the support of crutches and other external objects makes the exoskeleton system for lower limb rehabilitation training more stable and assists the wearer in walking rehabilitation training.

The specific plan is that the adduction and abduction angle of the hip joint on the swing side is 0 degrees in the under-abduction state.

The preferred scheme is that the step of adduction to meet the balance criterion of zero moment point includes (1) obtaining the plantar pressure data of the exoskeleton system; within the set interval. Based on the plantar pressure of the supporting leg, it is judged whether the supporting leg is inwardly positioned, that is, until the zero-moment point balance criterion is met. This control method is simple and effective.

In order to achieve the above-mentioned another purpose, the hip joint structure used in the exoskeleton system for lower limb rehabilitation training provided by the present invention includes adduction and abduction degree of freedom driving mechanism; Including the mounting base, left hip adduction drive arm, right hip adduction drive arm and driver; the left hip adduction drive arm is installed on the mounting base through the left hinge shaft, and can be adducted single around the axis of the left hinge shaft Reciprocating swing between the leg support position and the under-abduction position; the right hip adduction drive arm is installed on the mounting seat through the right hinge shaft, and can swing around the axis of the right hinge shaft between the adduction single-leg support position and the under-abduction position The driver is used to drive the swing side of the adduction drive arm of the two hip joints to maintain the under-abduction position, and the support side is adducted during the single-leg gait cycle.

Based on the structural design of the adduction and abduction driving mechanism of the hip joint, the adduction and abduction driving mechanism on the hip joint is configured as an abduction and abduction under-actuation mechanism, so that the exoskeleton system can guide the wearer to perform walking rehabilitation training. During the swinging process, the swinging leg is always kept in the under-abduction position during the swinging process, and the hip joint of the supporting leg is adducted at the same time, so that the overall center of gravity is shifted toward the supporting leg side to meet the zero-moment point balance judgment. According to the data, the wearer can effectively avoid the problem of rolling without the support of external objects such as crutches, so that the exoskeleton system for lower limb rehabilitation training constructed by the hip joint can more smoothly assist the wearer in walking rehabilitation training.

The specific scheme is that the driver includes a rotary driver, and two sets of intermittent motion mechanisms that are driven by the rotary driver to force the hip joint adduction drive arm to swing intermittently around the axis of the hinge shaft: the number of the rotary driver is one, and the rotating output shaft The main input gear is fixed on the top; the intermittent motion mechanism includes an output gear that is fixedly connected with the hip joint adduction drive arm to rotate synchronously, and a transition gear that meshes with the main input gear and the output gear at the same time; The double-link gear composed of complete gears, the complete gear meshes with the main input gear, and the incomplete gear meshes with the output gear; the teeth on the incomplete gears in the two sets of intermittent motion mechanisms are mutually exclusive to contact and mesh with the corresponding output gear, that is, At the same time, at most only one set of intermittent motion mechanism is driving the corresponding hip joint to adduct the driving arm to swing.

Based on the intermittent motion mechanism composed of the active incomplete gear and the driven complete gear in the gear set, the two hip joint adduction drive arms can be driven to swing intermittently, and can be in the less abduction position and adduction single according to requirements. The leg support position swings intermittently, and the corresponding position can be kept in this position because there is no swing driving force, and the two intermittent motion mechanisms are driven based on a single rotary driver, which can effectively improve the compact structure of the hip joint sex.

A more specific solution is that the driver also includes two locking mechanisms, which are respectively used to adduct the corresponding hip joint adduction drive arm that swings to the under-abduction position or the adduction single-leg support position. Selectively locked in this position. By setting the locking mechanism, the hip joint adduction drive arm can be supported and maintained by the locking mechanism in the support stage, effectively avoiding excessive load to the rotary driver, and improving the service life of the rotary driver.

A further solution is that the locking mechanism includes a control gear that meshes with the complete gear, a cam that is rotatably installed on the mounting base and is fixedly connected with the control gear to rotate synchronously, is mounted on the mounting base swingably around the axis of the hinge shaft, and The swing end is pressed against the curved guide part of the cam, and the locking link is hinged with one end of the swing top claw and the other end is hinged with the corresponding hip joint adduction drive arm; the curved guide part includes a small diameter lock The arc portion and the large-diameter locking arc portion; the swing top claw, the locking link, the hip joint adduction drive arm and the mounting seat constitute a hinged four-bar linkage mechanism with the mounting seat as a frame.

The cam mechanism is composed of cams with different radii of locking arc segments and swinging top claws, and provides support and retention force for the adduction drive arm of the hip joint through the locking link; and the cam is rotationally coupled with the transition gear through the control gear, So that the action of the locking mechanism is controlled by the rotary driver, the synchronous action of the locking mechanism and the driving arm can be well realized, that is, the control of the synchronous action of the locking mechanism and the adduction driving arm of the hip joint is realized through the mechanical structure, and the overall structure Simple and reliable.

A further solution is that the rotation of the two connecting rods on the hinged four-bar linkage mechanism is opposite; along the height direction of the lower limb rehabilitation training exoskeleton system, the dynamic hinge axis on the swing top claw is located between the upper fixed hinge axis and the corresponding hip joint. Between the movable hinge shafts on the retraction driving arm, the two hinge shafts on the swing top claw are located below the dynamic hinge shafts on the hip joint retraction drive arm; The hinge axes are all located on the side of the movable hinge axis on the corresponding hip joint adduction drive arm adjacent to the sagittal plane of the exoskeleton system, and the cam shafts are located on the side of the two hinge axes on the swing top claw adjacent to the sagittal plane; When the driving arm is in the less abducted position, the swing end is pressed against the locking arc of the large diameter; when the hip joint adduction driving arm is in the adducted single-leg support position, the swing end is pressed against the locking arc of the small diameter The rotation axis of the main input gear is located on the sagittal plane, and the hinge axes of the corresponding fixed hinge shafts on the two sets of intermittent motion mechanisms and the two locking mechanisms are arranged symmetrically with respect to the sagittal plane.

The preferred solution is that the less abducted position is the position where the adduction and abduction angle of the hip joint on the swing side is 0 degrees.

In order to achieve the above-mentioned still another purpose, the exoskeleton system for lower limb rehabilitation training provided by the present invention includes a control unit and a hip joint unit controlled by the control unit; the hip joint unit is the hip joint structure described in any of the above technical solutions.

The lower extremity rehabilitation training exoskeleton system based on the above-mentioned hip joint structure can more smoothly assist the wearer in walking rehabilitation training.

Description of drawings

1 is a perspective view of an embodiment of the lower limb rehabilitation training exoskeleton system of the present invention;

Fig. 2 is a perspective view of the hip joint adduction and abduction drive mechanism in an embodiment of the exoskeleton system for lower limb rehabilitation of the present invention;

Fig. 3 is a structural diagram of the hip joint adduction and abduction degree of freedom drive mechanism after omitting the baffle in the embodiment of the exoskeleton system for lower limb rehabilitation of the present invention;

Fig. 4 is a schematic diagram of the transition position when both adduction and adduction driving arms of the hip joint adduction and abduction degree of freedom driving mechanism in the embodiment of the exoskeleton system for lower limb rehabilitation of the present invention are in the adduction and abduction angle of 0 degrees;

Fig. 5 is a partial enlarged view of A in Fig. 4;

Fig. 6 is a partial enlarged view of B in Fig. 4;

Fig. 7 is the embodiment of the exoskeleton system for lower limb rehabilitation of the present invention. One hip joint adduction driving arm on the hip joint adduction and abduction degree of freedom driving mechanism is kept in the under-abduction position while the other hip joint adduction driving arm is in the Schematic diagram of the state when adducting the single-leg support position;

Fig. 8 is a schematic diagram of the adduction and abduction trajectory of the hip joint when controlling the embodiment of the lower limb rehabilitation training exoskeleton system of the present invention to walk;

Fig. 9 is a working flow chart of controlling the embodiment of the lower limb rehabilitation training exoskeleton system of the present invention to walk;

Fig. 10 is a schematic diagram of the position arrangement of the plantar pressure sensor arranged on the sole of the wearer's foot in the embodiment of the lower limb rehabilitation training exoskeleton system of the present invention;

Fig. 11 is a schematic diagram of ZMP simulation results when there is no adduction and abduction when controlling the lower limb rehabilitation training exoskeleton system embodiment of the present invention to walk;

Fig. 12 is a schematic diagram of ZMP simulation results when controlling the embodiment of the exoskeleton system for lower limb rehabilitation training of the present invention to adduct when walking.

Detailed ways

The present invention will be further described below in conjunction with embodiment and accompanying drawing.

Embodiment of exoskeleton system for lower limb rehabilitation training

Referring to FIG. 1 , the lower limb rehabilitation exoskeleton system of the present invention includes a control unit, a detection unit and an exoskeleton 1 . The control unit includes a processor and a memory, the detection unit outputs detection signals to the control unit, and the control unit outputs control signals to the driving mechanisms of the exoskeleton to drive the exoskeleton to guide the rehabilitation trainer's lower limbs to walk along a predetermined trajectory.

1 and 2, the exoskeleton 1 includes a waist wearing unit 11, a hip joint unit 12, a thigh rod 13, a thigh strap 14, a knee joint flexion and extension drive unit 15, a calf strap 16, a calf rod 17, and an elastic passive ankle joint. Unit 18 and exoskeleton plantar unit 19. The waist wearable unit 11 is used for fixing the exoskeleton system and the human waist; the hip joint unit 12 has the hip joint adduction and abduction drive mechanism 2, the hip joint flexion and extension drive mechanism 121 and the hip joint internal rotation and external rotation drive mechanism The mechanism 122 is used to control the actions of three degrees of freedom among the four degrees of freedom on the exoskeleton 1 . The straps are used to connect the leg bar and the human leg, so that the leg bar can drive the human leg to move along a predetermined track; the exoskeleton plantar unit 12 cooperates with the human foot.

2 to 7, the adduction and abduction degree of freedom driving mechanism 2 includes a mounting base 201, a baffle plate 202, a driving motor 203, a harmonic reducer 204, a left hip joint adduction drive arm 21, and a right hip joint adduction drive Arm 22 , main input gear 23 , left intermittent drive mechanism 3 , right intermittent drive mechanism 4 , left lock mechanism 5 and right lock mechanism 6 . The main input gear 203 is fixed on the rotary output shaft of the harmonic reducer 204 .

The left hip joint adduction drive arm 21 is installed on the mounting base 201 through the left hinge shaft 210 so that it can reciprocate and swing around the axis of the hinge shaft, and the right hip joint adduction drive arm 22 can revolve around the hinge shaft through the right hinge shaft 220. The axis of the reciprocating swing is installed on the mounting base 201.

The left intermittent drive mechanism 3 includes an output gear 33 and a transition gear 30 meshed with the main input gear 23 and the output gear 33 at the same time; the output gear 33 is fixedly connected with the left hip joint adduction drive arm 21 through the same hinge shaft 210 for synchronous rotation, In this embodiment, a flat key mechanism is used to fixedly connect the two with the hinge shaft 210, and the hinge shaft 210 is rotatably mounted on the mounting base 201 to realize the adduction of the left hip joint with the driving arm 21 and the output gear. 33 can be synchronously rotatably installed on the mounting base 201; the transition gear 30 is a duplex gear composed of a complete gear 31 and an incomplete gear 32. In this embodiment, the dedendum circles of the complete gear 31 and the incomplete gear 32, The addendum circle and gear teeth are equal in size; the complete gear 31 meshes with the main input gear 23, and the incomplete gear 32 meshes with the output gear 33, so that the driving motor 203 drives the main input gear 23 to rotate through the harmonic reducer 204, and then Drive the complete gear 31 to rotate and drive the incomplete gear 32 to rotate synchronously. When the tooth part 320 of the incomplete gear 32 contacts and meshes with the gear teeth of the output gear 33, it drives the left hip joint to adduct the driving arm 21 around the hinge shaft 210 Swing; the number of teeth reserved on the tooth portion 320 is selected according to the magnitude of the driving force and the structural strength of the gear. In this embodiment, only three teeth are reserved on the tooth portion 320 .

The right intermittent drive mechanism 4 includes an output gear 43 and a transition gear 40 meshed with the main input gear 23 and the output gear 43 at the same time; the output gear 43 is fixedly connected with the right hip joint adduction drive arm 22 through the same hinge shaft 220 for synchronous rotation, In this embodiment, a flat key mechanism is used to fixedly connect the two with the hinge shaft 220, through which the hinge shaft 220 is rotatably mounted on the mounting base 201, so as to realize the adduction of the right hip joint by the drive arm 22 and the output gear 43 It can be installed on the mounting base 201 synchronously and rotatably; the transition gear 40 is a duplex gear composed of a complete gear 41 and an incomplete gear 42. In this embodiment, the dedendum circles and tooth The top circle and gear teeth are equal; the complete gear 41 meshes with the main input gear 43, and the incomplete gear 42 meshes with the output gear 43, so that the drive motor 203 drives the main input gear 23 to rotate through the harmonic reducer 204, and then drives The complete gear 41 rotates to drive the incomplete gear 42 to rotate synchronously. When the tooth portion 420 of the incomplete gear 42 contacts and meshes with the gear teeth of the output gear 43, the driving arm 22 is moved around the hinge axis 220 with the right hip joint adduction. Swing; the number of teeth reserved on the tooth portion 420 is selected according to the driving force and the structural strength of the gear. In this embodiment, only three teeth are reserved on the tooth portion 420 .

The left locking mechanism 5 includes a cam 51, a control gear 52, a swing top claw 53 and a locking link 54; the cam 51 and the control gear 52 are respectively fixed on the hinge shaft 55 through a flat key mechanism, and are rotatable through the hinge shaft 55 It is installed on the mounting base 201, and the cam 51 and the control gear 52 can be fixedly connected to rotate synchronously, and the control gear 52 is meshed with the full gear 31, so that the drive motor 203 passes through the harmonic reducer 204, the main input gear 23, the transition The transmission train control cam 51 that the gear 30 and the control gear 52 constitutes rotates, and promptly the action of the left locking mechanism 5 is controlled by the drive motor 203; The axis is oscillatingly installed on the mounting base 201, and its oscillating end is pressed against the curved guide part of the cam 51. In this embodiment, the curved guide part is the outer contour surface 510 of the cam 51, and the outer contour surface 510 includes a small diameter The locking arc portion 512, the large-diameter locking arc portion 511 and the guide transition surface 513 connecting the two; the lower end of the locking link 54 is hinged with the middle part of the swing top claw 53 through the movable hinge shaft 57, and the upper end is hinged through the movable hinge. The shaft 58 is hinged with the left hip joint adduction drive arm 21; the swing top claw 53, the locking link 54, the left hip joint adduction drive arm 21 and the mounting seat 201 form the mounting base 201 as a frame, and the swing top claw 53 The adduction drive arm 21 of the left hip joint is a hinged four-bar linkage mechanism with the locking link 54 as a connecting rod. The swing direction of the arm 21 is opposite, that is, the rotation of the two connecting rods is opposite, which effectively improves the compactness of the locking mechanism in the X-axis direction as shown in FIG. 4 .

As shown in Figures 3 and 4, along the height direction of the lower limb rehabilitation training exoskeleton system, that is, along the Y axis as shown in Figure 4, during the action of the left locking mechanism 5, the movable hinge shaft 57 remains at the hinge position. Between the shaft 56 and the movable hinge shaft 58, the movable hinge shaft 57 and the hinge shaft 56 are all located below the dynamic hinge shaft 58, that is, the movable hinge shaft on the swing top claw 53 is located on it. The fixed hinge shaft and the adduction drive of the left hip joint Between the movable hinge shafts on the arm 21, and the two hinge shafts on the swing top claw 53 are all located below the movable hinge shafts on the left hip joint adduction drive arm 21.

Along the transverse direction of the lower limb rehabilitation training exoskeleton system, that is, along the X axis as shown in Figure 4, the dynamic hinge axis 57 and the hinge axis 56 are both located on the side of the dynamic hinge axis 58 adjacent to the sagittal plane 100 of the exoskeleton system, that is, swinging The two hinge axes on the top claw 53 are all located on the side of the moving hinge axis on the adduction drive arm 21 of the left hip joint adjacent to the sagittal plane 100; One side of the plane 100 , that is, the distance between the hinge axis 56 , the dynamic hinge axis 57 and the sagittal plane 100 in the X-axis direction is greater than the distance between the hinge axis 55 and the sagittal plane 100 in the X-axis direction.

The right locking mechanism 6 includes a cam 61, a control gear 62, a swing top claw 63 and a locking link 64; the cam 61 and the control gear 62 are respectively fixed on the hinge shaft 65 through a flat key mechanism, and are rotatable through the hinge shaft 65 It is installed on the mounting base 201, and the cam 61 and the control gear 62 can be fixedly connected to rotate synchronously. The control gear 62 meshes with the full gear 41, so that the drive motor 203 passes through the harmonic reducer 204, the main input gear 23, the transition The transmission train control cam 61 that gear 40 and control gear 62 constitutes rotates, and promptly the action of right locking mechanism 6 is controlled by driving motor 203; The axis is oscillatingly installed on the mounting seat 201, and its oscillating end is pressed against the curved guide part of the cam 61. In this embodiment, the curved guide part is the outer contour surface 610 of the cam 61, and the outer contour surface 610 includes The small-diameter locking arc portion 612, the large-diameter locking arc portion 611 and the guide transition surface 613 connecting the two; the lower end of the locking link 64 is hinged with the middle part of the swing top claw 63 through the movable hinge shaft 67, and the upper end is hinged through the movable hinge shaft 67. The hinge shaft 68 is hinged with the adduction drive arm 22 of the right hip joint; the swing top claw 63, the locking link 64, the right hip joint adduction drive arm 22 and the mounting seat 201 form the frame with the mounting seat as the frame, and the swing top pawl 63 The adduction driving arm 22 of the right hip joint is the hinged four-bar linkage mechanism with the locking link 64 as the connecting rod. The swing direction of the arm 22 is opposite, that is, the rotation of the two connecting rods is opposite, which effectively improves the compactness of the locking mechanism in the X-axis direction as shown in FIG. 4 .

As shown in Figures 3 and 4, along the height direction of the exoskeleton system for rehabilitation training of lower limbs, that is, along the Y axis as shown in Figure 4, during the action of the right locking mechanism 6, the movable hinge shaft 67 remains at the hinge position. Between the axis 66 and the movable hinge axis 68, the movable hinge axis 67 and the hinge axis 66 are all located below the movable hinge axis 68, that is, the movable hinge axis on the swing top claw 63 is located on the fixed hinge axis and the adduction drive of the right hip joint. Between the movable hinge shafts on the arm 22, and the two hinge shafts on the swing top claw 63 are all located below the movable hinge shafts on the adduction drive arm 22 of the right hip joint.

Along the transverse direction of the lower limb rehabilitation training exoskeleton system, that is, along the X axis as shown in Figure 4, the dynamic hinge axis 67 and the hinge axis 66 are both located on the side of the dynamic hinge axis 68 adjacent to the sagittal plane 100 of the exoskeleton system, that is, swing The two hinge axes on the top claw 63 are all located on the side of the moving hinge axis on the adduction drive arm 22 of the right hip adjacent to the sagittal plane 100; One side of the plane 100 , that is, the distance between the hinge axis 66 , the dynamic hinge axis 67 and the sagittal plane 100 in the X-axis direction is greater than the distance between the hinge axis 66 and the sagittal plane 100 in the X-axis direction.

As shown in Figure 4, the axis of rotation of the main input gear 23 is located on the sagittal plane 100, the hinge axis 220 and the hinge axis 210, the hinge axis of the transition gear 40 and the hinge axis of the transition gear 30, the hinge axis 65 and the hinge axis 55, The hinge axis 66 and hinge axis 56, the movable hinge axis 67 and 57, the movable hinge axis 68 and the movable hinge axis 58 are arranged symmetrically with respect to the sagittal plane 100, and the size parameters of the transition gear 40 and the transition gear 30 are the same. The size parameters of the output gear 43 , the output gear 33 , the control gear 62 and the control gear 52 are all the same.

The state shown in Figure 4 is that the left hip joint adduction drive arm 21 and the right hip joint adduction drive arm 22 are located at a position where the adduction and abduction angles are 0 degrees, that is, the legs on both sides are in an upright state and both feet are completely upright. Supported on the ground; at this time, as shown in Figure 3 to Figure 6, the tooth part 420 of the incomplete tooth 42 is in the forward position of the meshing position with the output gear 43 and is located below the contact area of the two gears, while the incomplete tooth The tooth part 320 of 32 is in the forward position of the meshing position with the output gear 33 and is located below the contact area of the two gears, and the swing end of the swing top claw 53 is pressed against the large-diameter locking arc 511 and the guide transition surface 513 and the swing end of the swing top claw 63 presses against the end of the large-diameter locking arc 611 adjacent to the guide transition surface 613 . In this state, if the drive motor 203 stops, then under the locking of the two locking mechanisms, the two hip joint adduction drive arms can be kept at this position, that is, the locking mechanism at this time is used to hold the hip joint The retracted drive arm is locked in this position.

In this embodiment, the process of driving the drive motor to drive the two hip joints to adduct the driving arm is as follows:

(1) When the initial state is as shown in Figure 4, and the drive motor 203 drives the main input gear 23 through the harmonic reducer 204 to first rotate clockwise and then counterclockwise:

(1.1) As the drive motor 203 drives the main input gear 23 to rotate clockwise, the complete gear 31 drives the incomplete gear 32 to rotate counterclockwise synchronously, and the control gear 52 drives the cam 51 to rotate clockwise to make the swing top The swing end of the claw 53 slides into the guide transition surface 513 to release the position locking effect on the adduction drive arm 21 of the left hip joint, and the tooth portion 320 is rotated with the incomplete gear 32 to enter into the tooth portion of the output gear 33 that is in contact with the mesh. position to drive the left hip joint adduction drive arm 21 to swing clockwise, that is, the left hip joint adduction drive arm 21 performs the hip joint adduction action, and the aforementioned unlocking action is earlier than the tooth portion 320 contacts with the tooth portion of the output gear 33 Engagement action; with the adduction of the left hip joint, the driving arm 21 swings clockwise at a predetermined angle until the tooth portion 320 is out of contact with the tooth portion of the output gear 33 and engages. In this embodiment, the angle of rotation is approximately 7 degrees; at this time , the swing end of the swing top claw 53 will slide over the guide transition surface 513 and press against the small-diameter locking arc portion 512, so as to lock the left hip joint adduction drive arm 21 in the downward swing position, thereby providing resistance to the overall gravity. The holding force, that is, the equivalent central angle of the guide transition surface 513 relative to the axis of the hinge shaft 55 is less than or equal to the aforementioned predetermined angle, which is less than or equal to 7 degrees in this embodiment, and the drive arm 21 swings clockwise when the left hip joint is adducted During the process, the adduction drive arm 21 of the left hip joint is swung clockwise, and the swing track of the swing end of the swing top pawl 53 is driven by the hinge four-bar linkage mechanism and the guide transition surface 513 just abuts against or separates without contact during the rotation process.

The incomplete gear 42 rotates counterclockwise synchronously, so that the tooth portion 420 on it will not be in contact with the output gear 43 to change the position of the right hip joint adduction drive arm 22, and the swing top can be driven by driving the cam 51 to rotate clockwise. The swing end of the pawl 63 continues to press against the large-diameter locking arc portion 611 , that is, the right locking mechanism 6 continues to provide locking and holding force for the adduction driving arm 22 of the right hip joint.

At this time, when the left hip joint adduction drive arm 21 is adducted to a predetermined angle, the right hip joint adduction drive arm 22 has been kept at a position where the adduction and abduction angle is 0 degrees, that is, the right hip joint adduction drive Arm 22 is in the underabducted position in this embodiment, and left hip adduction drive arm 21 is in the adducted single leg support position in this embodiment.

(1.2) Then, control the drive motor 203 to drive the main input gear 23 to rotate counterclockwise, then drive the incomplete gear 32 to rotate clockwise synchronously, and the tooth portion 320 is transferred to the position of contacting and meshing with the tooth portion of the output gear 33 to drive The adduction drive arm 21 of the left hip joint swings counterclockwise to reset at a position of 0 degrees in adduction and abduction; at the same time, the control gear 52 drives the cam 51 to rotate counterclockwise so that the swing end of the swing top claw 53 guides the transition surface 513 Sliding; with the adduction of the left hip joint, the driving arm 21 swings counterclockwise until the tooth part 320 turns over the aforementioned predetermined angle and is out of contact with the output gear 33 and no longer provides driving force. At this time, the left hip joint adduction driving arm 21 returns to its original position to the position where the adduction and abduction angle is 0 degrees, and the swing end of the swing top claw 53 slides to press against the large-diameter locking arc portion 511 to lock the lower swing position of the adduction and adduction driving arm 21 of the left hip joint. stop, thereby providing retention against the overall force of gravity.

The incomplete gear 42 rotates clockwise synchronously, the tooth portion 420 on it returns to the position where it will be in contact with the output gear 43, and the swing end of the swing claw 63 continues to press by driving the cam 61 to rotate counterclockwise On the large-diameter locking arc portion 611 , that is, the right locking mechanism 6 continues to provide locking and holding force for the adduction driving arm 22 of the right hip joint.

At this moment, both the adduction driving arm 21 of the left hip joint and the adduction driving arm 22 of the right hip joint are in the under-abduction position where the adduction and abduction angle is 0 degree as shown in FIG. 4 .

(2) When the initial state is as shown in Figure 4, and the drive motor 203 drives the main input gear 23 through the harmonic reducer 204 to first rotate counterclockwise and then clockwise:

(2.1) As the driving motor 203 drives the main input gear 23 to rotate counterclockwise, the incomplete gear 32 is driven to rotate clockwise synchronously, so that the teeth 320 on it will not engage with the output gear 33 and change the adduction of the left hip joint The position of the driving arm 21 is driven by driving the cam 51 to rotate counterclockwise so that the swing end of the swing top claw 53 continues to press against the large-diameter lock arc portion 511, that is, the left lock mechanism 5 continues to drive the left hip joint adduction Arm 21 provides lock retention.

As the driving motor 203 drives the main input gear 23 to rotate counterclockwise, the complete gear 41 drives the incomplete gear 42 to rotate clockwise synchronously, and the control gear 62 drives the cam 61 to rotate counterclockwise to make the swing of the top claw 63 The end slides into the guide transition surface 613 to release the position locking effect on the adduction drive arm 22 of the right hip joint, and the tooth part 420 enters the position of contacting and meshing with the tooth part of the output gear 43 as the incomplete gear 42 rotates to drive the right hip joint. The hip joint adduction drive arm 22 swings counterclockwise, that is, the right hip joint adduction drive arm 22 performs the hip joint adduction action, and the aforementioned unlocking action is earlier than the action of the tooth portion 420 contacting and meshing with the tooth portion of the output gear 43; With the adduction of the right hip joint, the driving arm 22 swings counterclockwise at a predetermined angle until the tooth portion 420 is out of contact with the tooth portion of the output gear 43. In this embodiment, the turned angle is approximately 7 degrees; The swing end of 63 will slide over the guide transition surface 613 and press against the small-diameter locking arc portion 612, so as to lock the driving arm 22 with hip joint adduction to continue to swing down, thereby providing a holding force against the overall gravity. That is, the equivalent central angle of the guide transition surface 613 relative to the axis of the hinge shaft 65 is less than or equal to the aforementioned predetermined angle, which is less than or equal to 7 degrees in this embodiment, and during the counterclockwise swing of the right hip joint adduction drive arm 22, by The right hip joint adduction drive arm 22 swings counterclockwise to drive the swing end swing track of the swing top claw 63 through the hinge four-bar linkage mechanism and the guide transition surface 613 just abuts against or separates without contact during the rotation process.

At this time, when the right hip joint adduction drive arm 22 is adducted to a predetermined angle, the left hip joint adduction drive arm 21 has been kept at a position where the adduction and abduction angle is 0 degrees, that is, the left hip joint adduction drive Arm 21 is in the underabducted position in this embodiment, and right hip adduction drive arm 22 is in the adducted single leg support position in this embodiment.

(2.2) Control the driving motor 203 to drive the main input gear 23 to rotate clockwise, then drive the incomplete gear 42 to rotate counterclockwise synchronously, and drive the right hip joint to adduct the drive through the tooth portion 420 contacting and meshing with the tooth portion of the output gear 43 The arm 22 swings clockwise to reset at the position of 0 degrees with the adduction and abduction angle; at the same time, the control gear 62 drives the cam 61 to rotate clockwise so that the swing end of the swing top claw 63 slides along the guide transition face 613; The adduction driving arm 22 swings clockwise until the tooth portion 420 rotates through the predetermined angle and is out of contact with the output gear 43 and no longer provides driving force. At this time, the right hip joint adduction driving arm 22 returns to the adduction and abduction angle 0 degree position, and the swing end of the swing top claw 63 slides to press against the large-diameter locking arc portion 611 to lock the lower swing position of the adduction drive arm 22 of the right hip joint, thereby providing resistance to the overall Gravity retention.

The incomplete gear 32 rotates counterclockwise synchronously, the tooth portion 320 on it returns to the position where it will be in contact with the output gear 33, and the swing end of the swing top claw 53 continues to press by driving the cam 51 to rotate clockwise On the large-diameter locking arc portion 511 , that is, the left locking mechanism 5 continues to provide locking and holding force for the adduction driving arm 21 of the left hip joint.

At this moment, both the adduction driving arm 21 of the left hip joint and the adduction driving arm 22 of the right hip joint are in the under-abduction position where the adduction and abduction angle is 0 degree as shown in FIG. 4 .

In the above two processes, the adduction and abduction trajectory of each leg of the hip joint is shown in Figure 8, that is, in about 50% of the cycle, its adduction and abduction angle is 0 degrees, and in the remaining about 50% The adduction action is carried out according to the predetermined track in the cycle, and the division of the aforementioned cycle is divided by the adduction and adduction driving arms 22 of the two hip joints as shown in Figure 4. The boundary line, that is, the adduction and abduction degree-of-freedom driving mechanism of the hip joint in this embodiment is an abduction-degree-of-freedom under-actuated mechanism.

The drive motor 203 and the harmonic reducer 204 together constitute the rotary driver in this embodiment, the rotary driver, the input gear 23, the left intermittent drive mechanism 3, the right intermittent drive mechanism 4, the left lock mechanism 5 and the right lock mechanism 6 together In this embodiment, the driver for driving the adduction driving arm 21 of the left hip joint and the adduction driving arm 22 of the right hip joint to swing according to the predetermined track is formed, that is, in this embodiment, there is a driver that cooperates with the adduction driving arm of each hip joint. The intermittent motion mechanism and the locking mechanism are used to synchronously control the intermittent swing motion of the adduction and abduction driving arms of the hip joint on each side based on the same rotary driver.

Referring to Fig. 9, in the process of using the exoskeleton system for lower limb rehabilitation training to assist the wearer in rehabilitation training, the walking control method includes identification step S1 and control step S2, that is, the processor in the control unit executes the computer program stored therein However, the recognition step S1 and the control step S2 can be implemented to control the exoskeleton system to guide the wearer to perform walking rehabilitation training.

In the identification step S1, the supporting side leg and the swinging side leg of the exoskeleton system in the single-leg gait cycle are identified.

It can be identified according to the control signals that are predetermined to control the flexion and extension actions of each joint.

Control step S2, controlling the hip joint on the swinging side to maintain a state of underabduction during the swinging movement of the swinging leg, and controlling the hip joint on the supporting side to adduct to meet the zero-moment point balance criterion during the single-leg support of the supporting leg .

In this embodiment, the full support of both legs is the initial state, that is, the adduction drive arms of the two hip joints are all in the under-abduction position as shown in Figure 4, and the left leg is used as the supporting side leg, while The right side leg is a swinging side leg, then control the drive motor 203 to drive the actions of each part according to the control method described in the aforementioned (1) to complete the action on the adduction and abduction degrees of freedom of the hip joint; After the action, return to the adduction drive arms of the two hip joints in the under-abduction position as shown in Figure 4, and then control the drive motor 203 to drive the various components according to the control method described in the aforementioned (2) to complete the hip joints in the position. Actions on the degree of freedom of adduction and abduction to complete the action of the next single-leg gait cycle. Alternately repeat the control methods described in (1) and (2) above to control the action of the adduction and abduction degree-of-freedom driving mechanism on the hip joint during the walking rehabilitation training process of the exoskeleton system.

In this embodiment, according to the pressure sensors arranged on the soles of both legs as shown in FIG. 192, the pressure sensor 193 and the pressure sensor 194 arranged on the heel of the foot detect the plantar pressure, and judge whether the supporting side hip joint moves to meet the zero-moment point balance criterion according to whether the plantar pressure is within the preset range.

The preset interval is based on multiple groups of normal people imitating the aforementioned walking gait, that is, in the single-leg gait cycle, the hip joint of the supporting leg is adducted and the hip joint of the swinging leg is kept in a less abducted position. In this implementation force, it is kept as The angle of adduction and abduction is roughly 0 degrees. Even if the swinging leg is roughly kept in an upright position, the relationship between the wearer's plantar pressure distribution range and the total weight is measured when the wearer does not have a roll problem, and is based on the wearer's and external weight during the control process. The total weight of the skeletal system obtains a corresponding pressure distribution interval as the aforementioned preset interval.

Wherein, the "single-leg gait cycle" is configured as a period between starting from the full-support state of both feet, starting the swing leg to swing to the next full-support state of both feet.

According to the adduction and abduction trajectory of the hip joint in the prior art as shown in Figure 8, the exoskeleton system is controlled to carry out walking rehabilitation training, and there will be no intersection between the ZMP trajectory and the plantar support surface of the supporting leg as shown in Figure 11. At this time, if there is no external support, there will be a roll.

According to the adduction and abduction track of this embodiment as shown in Figure 8, that is, the swing leg remains in the position of less than abduction and the support leg is adducted, the ZMP track and the plantar support of the support leg as shown in Figure 12 will appear. At this time, the zero-moment point equilibrium criterion is satisfied, and there will be no roll.

Embodiment of hip joint structure and embodiment of walking control method

The embodiment of the hip joint structure and the embodiment of the walking control method of the present invention have been described in the above embodiment of the lower limb rehabilitation exoskeleton system, and will not be repeated here.

Claims (6)

1. A hip joint structure for lower limb rehabilitation training exoskeleton system, including adduction and abduction degree of freedom driving mechanism; It is characterized in that the adduction and abduction degree of freedom driving mechanism is an abduction degree of freedom underactuated mechanism, including: mount; The adduction drive arm of the left hip joint is installed on the mounting seat through the left hinge shaft, and can swing back and forth between the adduction single-leg support position and the under-abduction position around the axis of the left hinge shaft; The adduction drive arm of the right hip joint is installed on the mounting seat through the right hinge shaft, and can swing back and forth between the adduction single-leg support position and the under-abduction position around the axis of the right hinge shaft; a driver for driving the swing side of the adduction drive arms of the two hip joints to maintain the under-abduction position and the support side to adduct during the single-leg gait cycle; the driver includes a rotary driver, and Two sets of intermittent motion mechanisms that are driven by the rotary driver to force the adduction drive arm of the hip joint to swing intermittently around the axis of the hinge shaft: the number of the rotary driver is one, and the main input gear is fixed on the rotary output shaft; The intermittent motion mechanism includes an output gear that is fixedly connected with the hip joint adduction drive arm to rotate synchronously, and a transition gear that meshes with the main input gear and the output gear at the same time; the transition gear is composed of a complete gear and an incomplete gear The complete gear meshes with the main input gear, and the incomplete gear meshes with the output gear; the teeth on the incomplete gears in the two sets of intermittent motion mechanisms are mutually exclusive with the Corresponding output gear contact mesh drive. 2. The hip joint structure according to claim 1, wherein the driver comprises: There are two locking mechanisms, which are respectively used to selectively lock the corresponding hip joint adduction drive arm that swings to the under-abduction position or the adduction single-leg support position at this position. 3. The hip joint structure according to claim 2, characterized in that: The locking mechanism includes a control gear that meshes with the full gear, a cam that is rotatably installed on the mounting seat and fixedly connected with the control gear to rotate synchronously, and is installed on the The swing top claw on the mounting base and the swing end is pressed against the curved guide part of the cam, and the locking link with one end hinged to the swing top claw and the other end hinged to the corresponding hip joint adduction drive arm. rod; The curved guide portion includes a small-diameter locking arc portion and a large-diameter locking arc portion; The swing top claw, the locking link, the hip joint adduction drive arm and the mounting seat constitute a hinged four-bar linkage mechanism with the mounting seat as a frame. 4. The hip joint structure according to claim 3, characterized in that: The steering of the two connecting rods on the hinged four-bar linkage mechanism is opposite; Along the height direction of the exoskeleton system for rehabilitation training of lower limbs, the dynamic hinge axis on the swing top claw is located between the upper fixed hinge axis and the dynamic hinge axis on the corresponding hip joint adduction drive arm, and the swing top claw The upper two hinge axes are located below the dynamic hinge axis on the adduction drive arm of the hip joint; Along the transverse direction of the exoskeleton system for rehabilitation training of lower limbs, the two hinge axes on the swing top claw are located on the side adjacent to the sagittal plane of the exoskeleton system on the adduction drive arm of the corresponding hip joint, and the camshaft is located on the side of the sagittal plane of the exoskeleton system. The two hinge axes on the swinging top claw are adjacent to the side of the sagittal plane; When the hip joint adduction driving arm is in the under-abduction position, the swing end is pressed against the large-diameter locking arc; when the hip joint adduction driving arm is in the adduction single-leg support position, The swing end is pressed against the small-diameter locking arc portion; The rotation axis of the main input gear is located on the sagittal plane, and the hinge axes of the corresponding fixed hinge shafts on the two sets of intermittent motion mechanisms and the two locking mechanisms are arranged symmetrically with respect to the sagittal plane. 5. The hip joint structure according to any one of claims 1 to 4, characterized in that: The under-abduction position is a position where the adduction and abduction angle of the hip joint on the swing side is 0 degrees. 6. An exoskeleton system for lower limb rehabilitation training, comprising a control unit and a hip joint unit controlled by the control unit; It is characterized by: The hip joint unit is the hip joint structure according to any one of claims 1 to 5.